Havin Trouble Cutting Threads Correctly

Just feed in with the cross slide. If the threads look good it clears everything but the angle of the compound.
 
Ray73 said:
Yes I used a protractor just now and my compound when set on 30 degrees is 30 degrees to the work piece sticking out of the chuck.
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I couldn't find your lathe on the HF site but the lathes that they show appear to have the compound feed parallel to the spindle axis when the dial reads "0". If that is the case for your lathe, you need to set an angle of 60 deg. Oftentimes, there is a secondary index mark that you use when the dial goes past the primary mark. If not, use a 30/60/90 drafting triangle or protractor to set the 60 degree angle. The angle isn't real critical as long as it is at least 60 deg. In a pinch, you can use the 60 deg. angle on the fishtail gauge.

Bob
 
That looks exactly like what I did once. It was because I was using a HSS threading tool that was about 3/8" square in a QCTP tool holder that had a V-groove in the bottom of the slot for holding round tools. Since the tool wasn't the full width of the slot, one edge dropped into that groove and tilted the bit. I had to put a piece of flat stock under it so it would sit correctly.
 
RJSakowski said:
I couldn't find your lathe on the HF site but the lathes that they show appear to have the compound feed parallel to the spindle axis when the dial reads "0". If that is the case for your lathe, you need to set an angle of 60 deg. Oftentimes, there is a secondary index mark that you use when the dial goes past the primary mark. If not, use a 30/60/90 drafting triangle or protractor to set the 60 degree angle. The angle isn't real critical as long as it is at least 60 deg. In a pinch, you can use the 60 deg. angle on the fishtail gauge.

Bob
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You are correct. I set it to 60 using a protractor and it cuts threads very nicely. Thank you for your reply.
 
I set the compound to 60 using a protractor because my lathe is numbered only to 40. It now cuts threads very nicely. Thanks to everyone for the reply's and advice. Now I'm on to practice some inside threading. Thanks again!

Ray
 
Ray73 said:
I set the compound to 60 using a protractor because my lathe is numbered only to 40. It now cuts threads very nicely. Thanks to everyone for the reply's and advice. Now I'm on to practice some inside threading. Thanks again!

Ray
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Glad that you have it sorted, Ray.

Now that you are correctly set for cutting threads, you may want to consider scribing a second index mark on your compound, say opposite the 40 degree line, so you can easily go to the correct compound setting for cutting threads.

Bob
 
Before you move anything now, find that 30 degree mark on the compound and scribe a mark on the cross slide to correspond to it.
 
I'm really going to throw a ringer in here. The angle of the compound rest only tells you where the cut will be generated from on the tool. If you use the recommended 29degrees you will cut on the side of the tool facing the chuck. With that said, ready guys, the angle is only to put less work on the tool. I cut threads from whatever angle the compound is at the time. You heard right, if it's set 90 degrees to the work you can cut good threads with it. You are just cutting with both sides of the tool. It won't hurt anything.

Being new at threading you should however stick to normal practice. You can experiment later.

"Billy G"
 
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Billy is right if you have the bit set right to the shaft your turning threads on it will be a even v cut no matter what angle the compound is set to. The case we have been talking about shows that it was the bit not being set right do to the holder tipping it which would cause the thread we saw in the picture.

Sent from my Venue8 3840 using Tapatalk
 
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I have been waiting some 30 years to hear someone say that. Kudos to you Handy4563.

"Billy G"
 
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